Yahoo Autos Will It Hurt My Battery If I Have The AC On When I Start It? Question Of The Day
Starting a car requires lots of energy from a battery, but can other things draw power at the same time and cause the battery to wear out faster?
Question: Does having your air conditioning on while you start a car engine shorten the battery life?
Answer: In a word, no – as long as your car was made in the mid-1980s or later. To draw an analogy, think about the Crawley family in Downtown Abbey, which always eats dinner before the butlers, footmen, maids and so forth. In this case, your car’s engine is the Crawleys and all the other components are Downton’s help staff.
Batteries in modern-day cars ensure that the engine always eats first, metaphorically speaking. When you start the engine in newer cars, anything that’s operated electrically – from the air conditioner fan to the radio – doesn’t draw power until after the engine is running.
Photo by Mercuryvapour / Flickr
“The maximum amount of output from a battery gets applied directly to starting the car,” says Tom Watson, vice president and technical fellow of powertrain, engineering and product development at Johnson Controls, the world’s largest manufacturer of automotive batteries. “The battery’s primary purpose is twofold. It needs to hold enough cranking performance to start the engine, then have enough reserve capacity so you can let it sit, then be confident that it can do the job the next time you start your car.”
The battery is arguably one of a car’s most important components, especially so because cars keep getting more and more complex. Some now have more than 40 on-board computers, said Watson. “The battery keeps all those computers functioning,” he said. “So it’s important that people pay attention to health of their battery.”
